During a severe storm with flooding in my area in June 2016, my telephone line and ADSL (internet) modem were damaged. The line measured a direct short-circuit and was duly fixed by the telecoms company (BT). The modem appeared completely dead, and I discovered that it rattled when I shook it. That can't be good!
Removing the cover revealed a single PCB:
There are a few components on the underside:
The telephone line is connected to a gas discharge tube (GDT) and two large capacitors. The capacitors have both exploded, and fragments of the cases were the source of the rattle.
Up to this point, I thought perhaps there may be a chance of repairing the modem. Unfortunately, a closer look revealed more damage.
The GDT is connected across the line, so would have done nothing to protect the electronics from a common-mode signal (i.e. one appearing on both lines). I suspect that a nearby lightning strike induced an energetic pulse in the line and caused the damage to the modem. It also probably damaged the electronics at the other end of the line, which is why the line was short-circuited.
I did take some photographs of the other major semiconductors in the modem.
The Broadcom BCM63168 is a "xDSL Integrated Access Device SoC", so would appear to contain the bulk of the modem itself plus the processor. The processor is a 400MHz dual-core MIPS CPU. Link to Broadcom site: bcm63168
The is a 64M x 16-bit DDR3 Synchronous DRAM (SDRAM):
Broadcom B50612E Ethernet PHY:
Wireless (WiFi) interface:
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